CHAPTER IV 

 THE BABCOCK TEST 



As has already been stated, the Babcock test 

 is responsible for much of the progress in dairy- 

 ing during the past twenty-five years. Its opera- 

 tion is so simple, the principles upon which it 

 is based are so easily understood, and its intelli- 

 gent use by dairymen is of such great importance 

 that it is deemed quite proper to give consider- 

 able space in this book to this test. 



How fat was formerly estimated. It will be 

 remembered that milk is composed of water, fat, 

 curd, sugar, and ash in varying proportions, and 

 that the fat globules are simply floating or sus- 

 pended in the milk serum. When these globules 

 rise to the top naturally they drag the curd and 

 other solids along with them and form a layer 

 at the top, rich in fat, which we call cream. 

 Before the invention of the Babcock test it was 

 the practice in some places to collect samples of 

 milk or cream, churn them, and melt the lumps 

 of butter in graduated tubes, from which the 

 amount of fat could be estimated. The purpose 

 of melting the churned butter was to collect the 



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